Asphalt mixer tip and shank assembly

ABSTRACT

An asphalt mixer tip and shank assembly in which a pugmill shank is secured midway between its ends to a mixer shaft. The shank comprises a separable hub with complementary shaft gripping hub halves clamped to the mixer shaft by bolts interengaging the separable members. A mixer tip is detachably secured at each end of the shank. Each mixer tip is formed with an ear and a recessed portion to receive the distal end of its associated separable member of the shank and is secured to the shank by a pin passing through the ear to urge the shank into the recessed portion of the mixer tip in fixed relation thereto. A slip-on shroud is mounted on each end of the shank.

Lutz

ASPHALT MIXER TIP AND SHANK ASSEMBLY June 12, 1973 PrimaryExaminer-Everette A. Powell, Jr. Attorney-Jack M. Wiseman [76] Inventor:Kenneth V. Lutz, 19782 Glen Brae Drive, Saratoga, Calif. 95070 ABSTRACT[22] Filed; 16 1971 An asphalt mixer tip and shank assembly in which apugmill shank is secured midway between its ends to a PP NO; 2081817mixer shaft. The shank comprises a separable hub with complementaryshaft gripping hub halves clamped to 52 U.S. c1. 416/210, 416/222 themixer Shaft by bolts ihterehgaging the separable 51 Int. Cl 801i 7/04members- A mixer tip is detaehebly Seemed at eaeh 58 Field 0f Search416/210, 211, 207, end of the shank- Eeeh mixer tip is formed with anear 416/204 259/109 178 and a recessed portion to receive the distal endof its associated separable member of the shank and is se- [56]References Cited cured to the shank by a pin passing through the ear tourge the shank into the recessed portion of the mixer 2 727 732 FATENTS416,207 X tip in fixed relation thereto. A slip-on shroud is um e a d fk 3,614,262 10/1971 Lutz 4l6/224 mounted each an o the Sham 16 Claims,12 Drawing Figures 1 38 /3 5 38 35 38 3 5 g r y r 12; f 35 7 ZL fflg l/gi gr 12w 2O 1h If Y 20 \1 r ao 30 i PAIENIEU Jim I 2 5 8MEI30F3 TIE. 1130 1 9 3% 9 V 7'? a 35 40b vj 'IG. 13

ASPHALT MIXER TIP AND SI'IANK ASSEMBLY BACKGROUND OF THE INVENTION Thepresent invention relates in general to asphalt mixers and moreparticularly to a pugmill shank and mixer tip assembly.

Heretofore, shanks were designated either left hand shanks or right handshanks. Such shanks were not interchangeable. While interchangeablemixer tips were disclosed in the patent to K. V. Lutz, U.S. Pat. No.3,614,262, issued on Oct. 19, 1971, for Asphalt Mixer Tips and in theBritish patent to Braham Brown Limited, No. 339,584, accepted on Dec.ll, I930, for Improvements In Mixers For Road Materials and the Like,such mixer tips were mounted on either a right hand shank or a left handshank. The British Pat. No. 339,5 84 and the patent to Guedel U.S. Pat.No. 1,555,964, issued on Oct. 6, 1925, for Blade For Asphalt And TheLike Mixers disclose shanks clamped to mixer shafts.

SUMMARY OF THE INVENTION A mixer tip comprising an ear and a confrontingrecessed portion to receive a shank. A pin received by the ear urgestheshank into fixed relation with the mixer tip.

A shank for attachment to a mixer shaft having a distal end received byan openingina mixer tip formed by an ear and a confronting recessportion.

By virtue of thepresent invention, both the mixer tip and the shank areinterchangeably useable either as a right hand or a left handmember.

A shroud that slips onto the distal end of the shank and is retainedthereon by a mixer tip, which is usable on either a right hand or a lefthand shank.

The present invention has reducedthe wear and tear on parts to make theassembly more durable and longer lasting.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, diagrammaticelevation view of a mixer shaft with associated shanks, mixer tips andshrouds of an asphalt mixer plant embodying the present invention.

FIG. 2 is a side elevation view of the shank embodying the presentinvention.

FIG. 3 is a plan view of the shank shown in FIG. 2.

FIG. 4 is aside elevation view of the mixer tip embodying the presentinvention.

FIG. 5 is a plan view of the mixer tip shown in FIG. 4.

FIG.'6 is an end elevation view of the mixer tip shown in FIGS. 4 and 5.

FIG. 7 is another side elevation view of the mixer tip shown in FIGS.4-7.

FIG. 8 is a horizontal section view taken along line 88 of FIG. 4.

FIG. 9 is a perspective view of the shank mounted on the mixer shaft andthe mixer tips mounted on the distal ends of the shank.

FIG. 10 is a side elevation view ofthe shank illustrated with slip-onshrouds embodying the present invention mounted thereon.

FIG. 1 l is a plan view of the shank illustrated with the shrouds shownin FIG. 11 mounted thereon.

FIG. 12 is a perspective view of the shank mounted on the mixer shaftand the mixer tips and slip-on shrouds mounted on the distal ends of theshank.

DESCRIPTION OF THE PREFERRED EMBODIMENT Illustrated in FIG. 1 is a rotor10 which is employed as an asphalt mixer for mixing ingredients ofaggregate and liquid asphalt or other cementing material commonly foundin asphalt mixing plants. The rotor 10 includes a drive shaft 12 with aplurality of shanks 20 of the present invention clamped thereto andprojecting radially therefrom.

For explanation purposes, it may be viewed that the dotted lines in FIG.1 represent the path of the mixture travelling toward an exit 16, atwhich point the mixture is to be discharged after the mixing operationis completed. The shanks 20 are universal or interchangeable and may beused either as a right hand shank or a left hand shank. For purposes ofillustration only, only the end shanks 20 are shown without pugmill tipsor shrouds. The intermediate shanks 20 are shown with pugmill tips 25 ofthe present invention. The center shanks 20 are complete with the mixertips 25 and slipon shrouds 30 of the present invention.

In operation, it is desirable that the rotor 10 simultaneously mix theliquid asphalt and aggregate while urging the mixture toward the exit16. The mixer tips 25 are universal or interchangeable and can be usedeither as a right hand pugmill tip or a left hand pugmill tip. Theslip-on shrouds 30, which are also universal or interchangeable, protectthe shanks 20 against excessive wear from the abrasive action of themixing material.

Illustrated in FIGS. 2 and 3 is the shank 20 of the present inventionwhich comprises a separable hub 35 having detachable hub halves 35a and35b. Confronting recessed portions 36a and 36b of the hub halves 35a and35b, respectively, form complementary jaws for gripping the drive shaft12. In the preferred embodiment, the cross-sectional area of the driveshaft is square or quadrature and the walls of the recesses 36a and 36bare shaped to accommodate a shaft with a square cross-sectional area.Angular adjustment of the shanks 20 on the shaft 12 can be made throughthe angular configuration of the walls of the recesses 36a and 36b.Suitable bolts and nuts 37 and 38 interengage complementary hub halves35a and 35b and clamp the shanks 20 in fixed relation to the drive shaft12 for rotation therewith. The nuts 38 are seated in recessed areas ofthe hub 35 to reduce the wear and tear thereon resulting from theabrasive action of the mixing ingredients.

Projecting radially outward from the hub half 35a is a shank blade 40athat is formed integrally therewith. In a similar manner, projectingradially outward from the hub half 35b is a shank blade 40b formedintegrally therewith. The shank blades 40a and 40b reduce incross-sectional area as the blades progress from the proximal end to thedistal end 41a and 41b. At the-distal ends 4l a and 41b of the shankblades 40a and 4%,

respectively, the cross-sectional areas are square or quadrature.

Illustrated in FIGS. 4-8 is the mixer tip 25 of the present inventionwhich comprises an arcuate top wall 45. Extendingfrom the top wall 45are end walls 46 and 47. It is the end walls 46 and 47 that provide theleading and trailing edges. The end wall 46 includes a pair of taperedsurfaces 46a and 46b that meet at a crown 46c, and the end wall 47includes a pair of tapered surfaces 47a and 47b that meet at a crown47c. A smooth front wall 48 joins the end walls 46 and 47. A rear wall50 also joins the end walls 46 and 47, and is disposed in parallel withthe front wall 48.

The rear wall 50 has projected outwardly therefrom an integrally formedear 55 which includes angularly disposed walls 55a and 55b (FIGS. 3 and8). The ear 55 is formed with a recess 55c that is defined by angularlydisposed walls that are right angle to one another. The walls definingthe recess 55c are parallel with the walls 55a and 55b. Formed in therear wall 50 is a recess 60 that confronts the recess 55c and is definedby angularly disposed walls that are right angle to one another. Thecross-sectional area of the recess 55c and 60 are square or quadratureand receive the distal end of the shank blade. As previously described,the distal end of the shank blade has a square or quadraturecrosssectional area. A bore 61 is formed in the ear 55 and passesthrough the walls 55a and 55b. A suitable spring steel roll pin 61 isreceived by the bore 61 and expands to fix the mixer tip 25 to the shank20.

The rear wall 50 is also formed with centrally located recessed, taperedwalls 62 and 63 that join in a vertex 64. Intermediate the ear 55 andthe walls 62 and 63 are recessed, right angle walls 65 and 66. The rearwall 50 is thus streamlined with smooth connecting surfaces to reducefriction and wear and tear.

The slip-on shroud 30 (FIGS. 10 and 11) is placed on the distal ends ofthe shank to protect the same against excessive wear and tear. Theshroud 30 comprises a sleeve 70 that slips onto the distal end of theshank 20 and slideably engages the blade of the shank. The opening ofthe sleeve 70 is of a size to receive the distal end of the shank. Theshroud 30 is limited to the extent of movement toward the proximal endof the shank by the tapered walls of the blade of the shank. Spacedbottom walls of the sleeve 70 provide guiding and retaining flanges forthe slide-on movement. lntegrally formed with the sleeve 70 is alongitudinally extending wall 71 that serves to protect the shankagainst the abrasive action of the mixing materials.

In use, the blades 40a and 40b are placed with the recesses 36a and 36bof the hub halves 35a and 35b confronting the drive shaft 12 and withthe walls of the recesses 36a and 36b embracing in clamping engagementthe drive shaft 12. Bolts 37 and nuts 38 secure the hub halves 35a and35b together to secure the shank 20 in fixed relation to the drive shaft12 for rotation therewith.

Now, the slip-on shrouds are placed on the distal ends of the shank 20.The mixer tips are then secured to the distal ends of the shank 20.Toward this end, the distal ends 41a and 41b of the shank 20 arereceived respectively by cars 55 of the mixer tips 25 and by confrontingrecesses 60 of the mixer tips 25. After the mixer tips 25 are mounted onthe shank 20, the roll pins 61' are inserted into the ears 55 forsecuring the mixer tips 25 to the shank 20. The mixer tips retain theshrouds on the shanks 20.

I claim:

1. A mixer assembly for attachment to a drive shaft comprising:

a. a shank comprising a hub for receiving the drive shaft to mount saidshank on the drive shaft for rotation therewith, and a blade projectingradially outward from said hub, said blade having a distal end; and

b. a mixer tip comprising an ear, said ear being formed with an openingextending in the general direction of said mixer tip for receiving thedistal end of said blade, and means on said mixer tip urging said mixertip in fixed relation with said blade for rotation with said shank,

c. said mixer tip being formed with a recessed portion confronting saidear, said opening in said ear being a recess confronting said recessedportion, said distal ends of said blade being received by said recessedportion and said recess of said ear, said recessed portion being formedwith right angular walls and said recess of said ear being defined byright angular walls and said distal end of said blade being formed witha contour conforming to the configuration of said walls.

2. A mixer tip as claimed in claim 1 and comprising a slip-on shroudmounted on said shank, said shroud comprising a sleeve for receiving thedistal end of said blade, said mixer tip being disposed radially outwardof said shroud for retaining said shroud on said shank.

3. A mixer assembly as claimed in claim 1 wherein the recess of saidrecessed portion and said recess of said ear are complementary anddefine a quadrature cross-sectional area and wherein the distal end ofsaid blade has a quadrature cross-sectional area.

4. A mixer assembly as claimed in claim 1 wherein said shank comprises asecond blade projecting radially outward from said hub, said hub beingseparable to form detachable first and second hub halves, said bladeprojecting from said first hub half and said second blade projectingfrom said second hub half, and comprising means interengaging said firstand second hub halves to urge said first and second hub halves intoclamping engagement with the drive shaft for securing said shank to saiddrive shaft.

5. A mixer assembly as claimed in claim 4 wherein said first and secondhub halves include confronting recesses defined by right angular wallsfor receiving the drive shaft.

6. A mixer tip comprising:

a. a top wall;

b. end walls extending from said top wall;

0. a front wall disposed between said end walls; and

cl. a rear wall disposed between said end walls, said rear wallcomprising an ear projecting outwardly therefrom, said ear being formedwith an opening for receiving the end of a blade extending in thegeneral direction of the mixer tip,

e. said rear wall being formed with a recessed portion confronting saidear, said opening in said ear being a recess confronting said recessedportion, the end of the blade being received by said recessed portionand said recess of said ear, said recessed portion being formed withright angular walls and said recess of said ear being defined by rightangular walls.

7. A mixer tip as claimed in claim 6 and comprising means on said earfor urging the blade in fixed relation with the mixer tip.

8. A mixer tip as claimed in claim 7 wherein said means is a pin ofexpansible material.

9. A mixer tip as claimed in claim 7 wherein the recess of said recessedportion and said recess of said ear are complementary and define aquadrature crosssectional area.

10. A mixer assembly as claimed in claim 1 wherein said means on saidmixer tip urging said mixer tip in fixed relation. with said blade forrotation with said shank is a pin of expansible material.

11. A mixer assembly for attachment to a drive shaft comprising:

a. a shank comprising a hub for receiving the drive shaft to mount saidshank on the drive shaft for rotation therewith, and a blade projectingradially outward from said hub, said blade having a distal end; and

b. a mixer tip comprising a first wall, said first wall being formedwith an opening extending in the general direction of said mixer tip forreceiving the distal end of said blade, and means on said mixer tipurging said mixer tip in fixed relation with said blade for rotationwith said shank,

c. said mixer tip being formed with a recessed portion in a second wallconfronting said first wall, said opening in said first wall being arecess confronting said recessed portion in said second wall, saiddistal ends of said blade being received by said recessed portion ofsaid second wall and said recess of said first wall, said recessedportion of said second wall being formed with right angular walls andsaid recess of said first wall being defined by right angular walls andsaid distal end of said blade being formed with a contour conforming tothe configuration of said right angular walls.

12. A mixer tip comprising:

a. a top wall;

b. end walls extending from said top wall;

c. a front wall disposed between said end walls; and

d. a rear wall disposed between said end walls, said rear wall beingformed with an opening for receiving the end of a blade extending in thegeneral direction of the mixer tip,

e. said rear wall being formed with a recessed portion confronting saidopening, the end of the blade being received by said recessed portionand said opening, said recessed portion being formed with right angularwalls and said opening being defined by right angular walls.

13. A mixer assembly as claimed in claim 11 wherein said means on saidmixer tip urging said mixer tip in fixed relation with said blade forrotation with said shank is a pin of expansible material.

14. A mixer tip as claimed in claim 13 and comprising a pin ofexpansible material on said rear wall for urging the blade in fixedrelation with said mixer tip.

15. A mixer assembly as claimed in claim 11 wherein said means on saidmixer tip urging said mixer tip in fixed relation with said blade forrotation with said shank is a pin disposed at right angles to said bladeand said mixer tip.

16. A mixer tip as claimed in claim 11 and comprising a pin on said rearwall disposed at right angles to said mixer tip for urging the blade infixed relation with said mixer tip.

1. A mixer assembly for attachment to a drive shaft comprising: a. ashank comprising a hub for receiving the drive shaft to mount said shankon the drive shaft for rotation therewith, and a blade projectingradially outward from said hub, said blade having a distal end; and b. amixer tip comprising an ear, said ear being formed with an openingextending in the general direction of said mixer tip for receiving thedistal end of said blade, and means on said mixer tip urging said mixertip in fixed relation with said blade for rotation with said shank, c.said mixer tip being formed with a recessed portion confronting saidear, said opening in said ear being a recess confronting said recessedportion, said distal ends of said blade being received by said recessedportion and said recess of said ear, said recessed portion being formedwith right angular walls and said recess of said ear being defined byright angular walls and said distal end of said blade being formed witha contour conforming to the configuration of said walls.
 2. A mixer tipas claimed in claim 1 and comprising a slip-on shroud mounted on saidsHank, said shroud comprising a sleeve for receiving the distal end ofsaid blade, said mixer tip being disposed radially outward of saidshroud for retaining said shroud on said shank.
 3. A mixer assembly asclaimed in claim 1 wherein the recess of said recessed portion and saidrecess of said ear are complementary and define a quadraturecross-sectional area and wherein the distal end of said blade has aquadrature cross-sectional area.
 4. A mixer assembly as claimed in claim1 wherein said shank comprises a second blade projecting radiallyoutward from said hub, said hub being separable to form detachable firstand second hub halves, said blade projecting from said first hub halfand said second blade projecting from said second hub half, andcomprising means interengaging said first and second hub halves to urgesaid first and second hub halves into clamping engagement with the driveshaft for securing said shank to said drive shaft.
 5. A mixer assemblyas claimed in claim 4 wherein said first and second hub halves includeconfronting recesses defined by right angular walls for receiving thedrive shaft.
 6. A mixer tip comprising: a. a top wall; b. end wallsextending from said top wall; c. a front wall disposed between said endwalls; and d. a rear wall disposed between said end walls, said rearwall comprising an ear projecting outwardly therefrom, said ear beingformed with an opening for receiving the end of a blade extending in thegeneral direction of the mixer tip, e. said rear wall being formed witha recessed portion confronting said ear, said opening in said ear beinga recess confronting said recessed portion, the end of the blade beingreceived by said recessed portion and said recess of said ear, saidrecessed portion being formed with right angular walls and said recessof said ear being defined by right angular walls.
 7. A mixer tip asclaimed in claim 6 and comprising means on said ear for urging the bladein fixed relation with the mixer tip.
 8. A mixer tip as claimed in claim7 wherein said means is a pin of expansible material.
 9. A mixer tip asclaimed in claim 7 wherein the recess of said recessed portion and saidrecess of said ear are complementary and define a quadraturecross-sectional area.
 10. A mixer assembly as claimed in claim 1 whereinsaid means on said mixer tip urging said mixer tip in fixed relationwith said blade for rotation with said shank is a pin of expansiblematerial.
 11. A mixer assembly for attachment to a drive shaftcomprising: a. a shank comprising a hub for receiving the drive shaft tomount said shank on the drive shaft for rotation therewith, and a bladeprojecting radially outward from said hub, said blade having a distalend; and b. a mixer tip comprising a first wall, said first wall beingformed with an opening extending in the general direction of said mixertip for receiving the distal end of said blade, and means on said mixertip urging said mixer tip in fixed relation with said blade for rotationwith said shank, c. said mixer tip being formed with a recessed portionin a second wall confronting said first wall, said opening in said firstwall being a recess confronting said recessed portion in said secondwall, said distal ends of said blade being received by said recessedportion of said second wall and said recess of said first wall, saidrecessed portion of said second wall being formed with right angularwalls and said recess of said first wall being defined by right angularwalls and said distal end of said blade being formed with a contourconforming to the configuration of said right angular walls.
 12. A mixertip comprising: a. a top wall; b. end walls extending from said topwall; c. a front wall disposed between said end walls; and d. a rearwall disposed between said end walls, said rear wall being formed withan opening for receiving the end of a blade extending in the generaldirection of the mixer tip, e. said rear wall being formed with arecessed portion confronting said opening, the end of the blade beingreceived by said recessed portion and said opening, said recessedportion being formed with right angular walls and said opening beingdefined by right angular walls.
 13. A mixer assembly as claimed in claim11 wherein said means on said mixer tip urging said mixer tip in fixedrelation with said blade for rotation with said shank is a pin ofexpansible material.
 14. A mixer tip as claimed in claim 13 andcomprising a pin of expansible material on said rear wall for urging theblade in fixed relation with said mixer tip.
 15. A mixer assembly asclaimed in claim 11 wherein said means on said mixer tip urging saidmixer tip in fixed relation with said blade for rotation with said shankis a pin disposed at right angles to said blade and said mixer tip. 16.A mixer tip as claimed in claim 11 and comprising a pin on said rearwall disposed at right angles to said mixer tip for urging the blade infixed relation with said mixer tip.